Pill-Cam spots internal affairs

Despite impressive advances in medical imaging systems, sometimes there is no way to diagnose a disease other than to look inside the body.

This has long been an arduous and unpleasant experience for patients, especially sufferers of digestive disorders. Diagnosing diseases of the upper gastro-intestinal tract — the oesophagus and stomach — can often only be done using endoscopes which patients have to swallow; a process so unpleasant that sedation and anaesthetics are usually needed.

But an easier option is likely to be available soon. Researchers in Israel and Europe are developing a disposable probe containing a tiny camera enclosed in a smooth housing less than an inch across, which doctors will be able to steer around the oesophagus and stomach using a magnetic controller— with little or no discomfort to patients. Even better, the developers believe the system could be cheaper than classical endoscopy.

Swallowable cameras have been used in gastro-intestinal surgery for almost a decade and one of the pioneers in the field, Israeli firm Given Imaging, is one of the partners in the latest research.

The current generation of cameras is housed in passive capsules that cannot be controlled once inside the body. The journey from mouth to stomach takes only four seconds and and cameras simply fall directly to the floor of the stomach.

‘The existing Given Pill-Cam is a good product,’ said Frank Volke of the Fraunhofer Institute for Biomedical Engineering in Sankte Ingbert, Germany, who has developed the steering system for the new camera. ‘It works in the oesophagus to some degree, but not in the stomach because there’s no way to direct it to the region where you need images.

‘It is particularly useful in the intestine and the colon because these are essentially one-dimensional tubes so the body’s peristaltic action moves the camera along smoothly and slowly.’

The results gained from these cameras have been so useful that the EU is sponsoring an important project to develop the technology further. Called NEMO (nano-based capsule endoscopy with Molecular imaging and Optical biopsy), the project has a budget of €4.7m (almost £4m) — of which the EU is providing €2.8m — and combines hardware and biological nanotechnology.

The latter part involves developing ‘nanocontainers’ based on long-chain oily molecules. These carry molecules on their surface that recognise and latch on to malignant cancer cells and contain a dye, which makes these cells visible.

A vital part of the project is a system that can search the gastro-intestinal tract for these dyed areas, and that is where swallowable cameras come in.

Volke’s team is part of a consortium including Given, which is providing the camera and its swallowable housing; and Anglo-Swedish electronics company Zarlink, which is developing a wireless transmission system to transfer images from the camera.

Volke explained that being able to control the camera will allow doctors to diagnose a wider range of diseases. ‘At the moment, if you want to look at the area where there is acid reflux from the stomach which can cause oesophageal cancer, there’s no way to stop a camera and look left and right to study the region in detail — you have to use traditional endoscopy.

‘With the new system, the patient will simply swallow a camera and feel no discomfort as their doctor moves it around.’